The University of Minnesota Islet Cell Resource (ICR) is well established. It is located in the Minnesota Molecular and Cellular Therapeutics Facility, a 36,000 sq ft facility dedicated to the manufacture of biologics in compliance with FDA's current Good Manufacturing Practices (cGMP) regulations. Staff working at this ICR has trained numerous visiting scientists, prepared 420 human islet products since 1996, made 250 islet shipments to 77 investigators since 1998 (totaling approximately 11 million islet equivalents), and manufactured 33 human islet products transplanted into 24 type 1 diabetic subjects enrolled in 4 Phase l/ll clinical trials. Of these 24 subjects, 21 became insulin-independent posttransplant (2 of the other 3 received a single islet infusion), indicating that techniques for preparing high-quality islet products are established. To build on these accomplishments and to continue the ICR we propose the following Specific Aims: Specific Aim #1: To distribute human islet products - manufactured and characterized in adherence to cGMP regulations - to eligible clinical investigators for approved transplantation protocols. Specific Aim #2: To distribute human islet products to eligible basic scientists for approved laboratory research studies according to allocation algorithms implemented by the Administrative and Bioinformatics Coordinating Center (ABCC). Specific Aim #3: To develop improved methods for assessment of human islet products and employ standardized measures to identify characteristics of such products that are predictive of clinical efficacy. Specific Aim #4: To optimize pancreas procurement, preservation, and processing procedures as well as islet storage and shipment protocols based on islet product testing prospectively validated in Aim #3. Specific Aim #5: To support the overall mission of the NCRR ICRs Program by coordinating activities with other ICRs and the Steering Committee; interacting with the ABCC on design and statistical evaluation of planned studies; transmitting islet assessment, basic laboratory, and clinical data to the ABCC in a timely manner; and by sharing patentable concepts with the Steering Committee members for use by other ICRs. Successful completion of the proposed work will further i) basic research on human islet beta cell biology, cytoprotection, function, imaging, immunomodulation, magnetic labeling, microgravity, replication, revascularization, transcriptional and translational regulation, transfection and transduction as well as ii) clinical research on the safety and efficacy of islet transplantation. Collectively, the proposed ICR will aid the development of novel and improved diagnostics and therapeutics for type 1 and type 2 diabetes, thereby improving the health and well-being of people afflicted with this challenging disease.